commit-atomically

name	commit-atomically
description	How to make logically atomic git commits. Use when a product increment is complete. Always ensure code compiles, passes fast tests, and passes linters and formatters defined by the repo instructions, AGENTS.md or DEVELOPING.md.

Commits

• Make small, logically independent commits.
• Separate unrelated changes (whitespace, style, bug fixes, perf) into different commits.
• If multiple files are changed for one logical change, keep them in one commit.
• If a later commit depends on an earlier one, note "this depends on commit cafe101 (where cafe101 is the 7-hex character commit hash)" in the body.

Refactoring commits

When applying coding standard rules, each rule is its own logically independent commit. For example, the following are separate refactoring commits:

• Replace magic numbers with named constants
• Eliminate any type occurrences
• Move nested type declarations to module scope
• Enforce line-length limit
• Remove "what" comments

Each refactoring commit may change multiple files, but should address only one rule across all files. This isolates the risk: if a refactoring accidentally breaks untested behaviour, bisect identifies exactly which rule caused it.

Commit message

• Follow the Conventional Commits v1 specification unless otherwise specified.
• Use type(scope): subject with scope optional; start the subject with a verb.
• Add a blank line before the body when you include one.
• If the change is a workaround, link to the known issue.
• If the commit is a change to agent instructions, copilot-instructions.md, AGENTS.md, or CLAUDE.md, use agents: as the type prefix.

Execution

• Always ensure code compiles, passes fast tests, and passes linters and formatters defined by the repo instructions, AGENTS.md or DEVELOPING.md.
• Proceed to make commits on the current branch without asking for approval.

Conventional Commits v1 Specification

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.

1. Commits MUST be prefixed with a type, which consists of a noun, feat, fix, etc., followed by the OPTIONAL scope, OPTIONAL !, and REQUIRED terminal colon and space.
2. The type feat MUST be used when a commit adds a new feature to your application or library.
3. The type fix MUST be used when a commit represents a bug fix for your application.
4. A scope MAY be provided after a type. A scope MUST consist of a noun describing a section of the codebase surrounded by parenthesis, e.g., fix(parser):
5. A description MUST immediately follow the colon and space after the type/scope prefix. The description is a short summary of the code changes, e.g., fix: array parsing issue when multiple spaces were contained in string.
6. A longer commit body MAY be provided after the short description, providing additional contextual information about the code changes. The body MUST begin one blank line after the description.
7. A commit body is free-form and MAY consist of any number of newline separated paragraphs.
8. One or more footers MAY be provided one blank line after the body. Each footer MUST consist of a word token, followed by either a : or # separator, followed by a string value (this is inspired by the git trailer convention).
9. A footer's token MUST use - in place of whitespace characters, e.g., Acked-by (this helps differentiate the footer section from a multi-paragraph body). An exception is made for BREAKING CHANGE, which MAY also be used as a token.
10. A footer's value MAY contain spaces and newlines, and parsing MUST terminate when the next valid footer token/separator pair is observed.
11. Breaking changes MUST be indicated in the type/scope prefix of a commit, or as an entry in the footer.
12. If included as a footer, a breaking change MUST consist of the uppercase text BREAKING CHANGE, followed by a colon, space, and description, e.g., BREAKING CHANGE: environment variables now take precedence over config files.
13. If included in the type/scope prefix, breaking changes MUST be indicated by a ! immediately before the :. If ! is used, BREAKING CHANGE: MAY be omitted from the footer section, and the commit description SHALL be used to describe the breaking change.
14. Types other than feat and fix MAY be used in your commit messages, e.g., docs: update ref docs.
15. The units of information that make up Conventional Commits MUST NOT be treated as case sensitive by implementors, with the exception of BREAKING CHANGE which MUST be uppercase.
16. BREAKING-CHANGE MUST be synonymous with BREAKING CHANGE, when used as a token in a footer.